x(t) = 20cos(2π*40t-0.4π)

x(t) = exp(-8πt)

x[n] = exp(cos(2πn/5))

x[n] = u[n] + u[-n]

x[n] = u[n] - u[-n] + 5δ[n]

Many thanks in advance.

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- Oct 6th 2011, 02:08 PMessedraAre these trigonometric functions even or odd?
x(t) = 20cos(2π*40t-0.4π)

x(t) = exp(-8πt)

x[n] = exp(cos(2πn/5))

x[n] = u[n] + u[-n]

x[n] = u[n] - u[-n] + 5δ[n]

**Many thanks in advance.** - Oct 6th 2011, 02:27 PMskeeterRe: Are these trigonometric functions even or odd?
- Oct 6th 2011, 03:02 PMessedraRe: Are these trigonometric functions even or odd?
- Oct 6th 2011, 03:18 PMskeeterRe: Are these trigonometric functions even or odd?Quote:

x(t) = 20cos(2π*40t-0.4π)

$\displaystyle x(-t) = 20 \cos(-80\pi t - 0.4\pi) = 20\cos[-(80\pi t + 0.4\pi)] = 20 \cos(80\pi t + 0.4\pi)$

final result ... x(-t) is not equal to x(t) or -x(t) ... x(t) is neither even or odd - Oct 6th 2011, 03:19 PMPlatoRe: Are these trigonometric functions even or odd?
Sometimes one must just have some prior information.

The function $\displaystyle \cos(x)$ is even and $\displaystyle \sin(x)$ is odd.

On the other hand, you should be able**to prove**that $\displaystyle f(x)=|x|$ is even.

Can you show that $\displaystyle f(x)=e^x$ is**neither even nor odd**? - Oct 6th 2011, 03:26 PMessedraRe: Are these trigonometric functions even or odd?
- Oct 6th 2011, 03:33 PMPlatoRe: Are these trigonometric functions even or odd?
- Oct 6th 2011, 03:35 PMessedraRe: Are these trigonometric functions even or odd?
Oh, I see now. It's simple as cake. Thank you...